Bottle cap



Nov. 19, 1946. T. J. VAN ALSTYNE BOTTLE CAP Filed April 5, 1944 Patented Nov. 19, 1946 UNITED STATES PATENT OFFICE BOTTLE CAP Thomas J. Van Alstyne, Portland, Oreg.

Application April 5, 1944, Serial No. 529,601

. 1 Claim.

This invention relates generally to closures for milk bottles and particularly to a bottle cap.

The main object of this invention is to devise a paper bottle cap of the type including a lifting tab which will render unnecessary the use of the conventional wire staple ordinarily employed to strengthen the cap at the lifting side of the tab.

The second object is to produce a cap of the class described which will eliminate any possibility of a rust formation, at the same tim conserving metal as well as lessening the cost of the cap itself.

I accomplish these and other objects in the manner set forth in the following specification as illustrated in the accompanying drawing, in which:

Fig. 1 is a plan of the improved form of cap.

Fig. 2 is an enlarged section taken along the line 2-2 in Fig. 1.

Fig. 3 is an enlarged view taken along the line 3-3 in Fig, 1.

Fig. 4 is a still larger magnification of a fragmentary cross section taken along the line 4-4 in Fig. 1, showing the tab raised.

Referring in'detail to the drawing, there is shown a circular disc 1!] of a specially prepared paper board having definite laminations II and i2 providing a distinct separating quality adapted to facilitate the raising of the flap l3 without undue loss in tensile strength. The usual thumb notch I l is also provided. Caps of this type are in common use and are usually reinforced by means of a metal staple. Such staples are not only difficult to obtain but require special equipment for applying same, and often result in the formation of rust due to the continued presence of moisture.

In the practice of my invention, instead of employing a metal staple, I prefer to strike a row of partial perforations it along the hinge line I6,

and extending beyond the limits thereof. These perforations are preferably short lines normal to the hinge line it, although they may assume other shapes without departing from the spirit of this invention.

The functions of theperforations 15 are threefold. First, it scores the tab l3 along the hinge line it, insuring a straight bend, and naturally a greater resulting strength, and secondly, it turns the fibres from the lamination II into the lamination I2, thereby riveting or tacking the laminations together along the hinge line l6, and thirdly, it divides the breadth of the relatively weak hinge material into a plurality of narrow strips of greater density occasioned by the displacement of the material in the slots at the same time prevents a continuous tear.

While I have thus illustrated and described my invention, it is not my intention to be limited to the precise form of cap or partial perforation illustrated herein, but it is my intention to cover all such forms and modifications of the device as fall fairly within the appended claims.

I claim:

A paper milk bottle cap consisting oftwo plies of paper forming a circular disc, one of said plies having a semi-circular perforation formed therein and having a plurality of pointed perforations extending along the diameter of said semi-circular perforation to form a hinge line therefor, said pointed perforations extending into the second ply and serving to unite the plies along the hinge line thereof.

THOMAS J. VAN ALS'I'YNE. 

